The product rollout was done with little fanfare: a soft launch followed by an extremely long beta, even longer than the one for Google Gmail. We’re actually still in beta, though everyone agrees the product is terrific.

And talk about green! It practically defined the term.

People can’t get enough of Earth. It’s a totally immersive experience and a platform for an impressive array of apps. Check out Art and Music. Their databases and functionality are way deeper than iTunes and YouTube. Spend some time with Cities, Forests, and Oceans, all in stunning 3-D. Wow. Into social networks? Families and Communities outclass Farmville, Facebook, and Second Life in terms of multiuser involvement.

In this critic’s humble opinion, Earth is easily one of the Top 10 must-haves of the eon.

Earth Day commemorates our planet for good reason. Without our blue-green orb, life would be bleak. We’re talking cold, airless, meteor-pocked bleak. Earth is our comfortable home in an unforgiving cosmos. It occupies the Goldilocks position in the solar system – not too far from the sun and not too close, protected from asteroids by Jupiter and Saturn. It’s the perfect garden for biology.

Cherishing and protecting the home planet is the least we can do. (A Monitor special report on the use of carbon offsets indicates some of our methods are falling short.) Here’s the embarrassing part, though: We’ve enjoyed Earth’s hospitality for 4.5 billion years but have been celebrating its special day for only 40. Considering how long it’s been around and how fond of it we are, that’s woeful.

The first Earth Day – April 22, 1970 – was a memorably unifying moment after the tumult of the 1960s. You didn’t need to be for or against the Vietnam War to mark Earth Day. Consciousness had been slowly rising for years. Henry David Thoreau, John Muir, Aldo Leopold, and Rachel Carson had promoted conservation and early environmentalism. The Boy and Girl Scouts taught generations to “take only photographs, leave only footprints.” Even Woodstock, with its “get back to the garden” vibe contributed.

But perhaps the most powerful impetus for Earth Day was the photo that Apollo 8 astronaut William Anders took of our gorgeous planet rising over the rocky gray surface of the moon. “Earthrise,” as the photo was dubbed, was a revelation.

Posters appeared everywhere. Life magazine called it one of 100 photos that changed the world. The poet Archibald MacLeish was so moved that he penned these immortal words: “To see the earth as we now see it, small and blue and beautiful in that eternal silence where it floats, is to see ourselves as riders on the earth together, brothers on that bright loveliness in the unending night – brothers who see now they are truly brothers.”

Honoring Earth got us outside our parochial disputes, if only for a day. So, thank you, big ‘E’ Earth. And we might as well thank little ‘e’ earth as well, which variously means the firmament, our present state of existence, and that sweet layer of humus that makes magic happen this time of year. Spading up spring soil, tucking tomato plants in the ground, and watching the Northern Hemisphere leaf out in late April tangibly connects us with our planet.

So breathe deep. Earth probably has only 1.5 billion more years before an enlarging sun makes it uninhabitable, at which point its product life expires. It will have been a good run. Depending on where humans are at that point, April 22 should still honor the place we got our start.John Yemma is the editor of The Christian Science Monitor.